-LRB- CNN -RRB- -- Gas prices have dropped more than 7 cents over the past two weeks , but risen in some regions stricken by Superstorm Sandy , according to a survey published Sunday .

The new national average for regular gasoline is $ 3.47 -- down more than 36 cents over the past six weeks , the Lundberg Survey found .

`` This latest decline comes mostly from weak gasoline demand , '' said publisher Trilby Lundberg , `` both because we are in the lower demand season and have also lost our daylight saving time . Losing that puts a damper on driving . ''

Sandy 's impact in the Northeast lowered demand as well , since many people were stuck at home , unable to drive .

Map : See images of destruction , recovery across the East Coast

But because there was also `` great difficulty getting fuel to the end user point , '' gas prices went up in some of those same areas , she said .

The highest average price found by the latest survey was $ 4.18 for New York 's Long Island . That average was up 26 cents from two weeks earlier .

Long Island generally has higher prices than the national average due to taxes .

The Lundberg Survey tallies prices at thousands of gas stations nationwide .

Good news should lie ahead for consumers around the country , Lundberg said .

`` Pump prices may well drop some more form here -- unless crude oil prices get seriously spooked by Middle East conflict or another geopolitical issue . ''

The current nationwide average is 9cents above the average a year ago , `` whereas most of this year it 's been more like 16 cents , '' Lundberg said .

The city with the lowest average in the latest survey was Memphis , at $ 3.04 .

Here are average prices in some other cities :

San Diego - $ 3.80

Seattle - $ 3.49

Las Vegas - $ 3.57

Denver - $ 3.35

El Paso - $ 3.36

St. Louis - $ 3.14

Boston - $ 3.69

Atlanta - $ 3.24

Miami - $ 3.42

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The average nationwide gasoline price is down 7 cents over 2 weeks , a survey says

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But prices are up in some areas hit by Superstorm Sandy , the Lundberg Survey reports

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Long Island had the highest average in the latest survey

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Memphis had the lowest